Our heroes are battling the fearsome Monster of the Week. Maybe it's got acid for blood, or More Teeth than the Osmond Family, or can violate the laws of physics with ease. But gradually our heroes realize something even more terrifying. This creature isn't just some mindless predator. In fact, it could be just as smart as they are... During discussions of this trope, the building and agriculturalactivities of ants may come up. It can evoke What Measure Is a Non-Human? to the viewers, often involuntarily, whenever the monster turns out to be as intelligent as a human being (i.e. pretty likely sapient). Nevertheless, the existence of this trope can mean that the antagonist had a motivation or goal simple enough to be mistaken for the behavior of a mere animal, so that many of its scenes could be acted by a Non-Malicious Monster without much difference. Until it does something unexpected. Smarter Than You Look and Obfuscating Stupidity are the human equivalents. Not Even Human is this trope's inverse (a thing that seemed to have intelligence at first is revealed not to). See also dehumanization for when non-human creatures’ ability to think intelligently is dismissed because they are not human. The Non-Malicious Monster is an aversion, a creature that is led by instinct and not any advanced thought. Compare Monster Is a Mommy, similar in terms of humans underestimating the motives of "monsters". See also Super-Persistent Predator and Suspiciously Stealthy Predator.